Add Watermark to PDF
Place a text watermark in the middle of every page — set the wording, size, opacity and angle.
Done
How to watermark a PDF
- Drop the PDF onto the box above, or click it to browse. One document at a time.
- Type the wording. CONFIDENTIAL is filled in to start with; DRAFT, COPY, NOT FOR DISTRIBUTION or a client's name work just as well, up to 80 characters.
- Set the font size — anywhere from 8 to 200 points, 50 by default — and the opacity, which runs from 10% to 100% and starts at 30%.
- Choose the angle: diagonal at 45 degrees, the classic stamped look, or horizontal straight across the middle.
- Press “Add Watermark”. Every page is stamped in grey bold text, centred, and the file downloads with -watermarked added to its name.
What people use it for
A watermark is mostly about setting expectations. It tells whoever opens the document what it is, what stage it is at, and where it came from — before they read a word of it.
- Marking a contract or proposal as DRAFT so nobody signs the wrong version.
- Stamping a client's name across a design or report sent for review, so a leaked copy is traceable.
- Labelling internal papers CONFIDENTIAL before they go to a wider circulation list.
- Marking scanned certificates or diplomas as COPY so they are not mistaken for the original.
- Adding a photographer's or studio name to a PDF portfolio sent to a prospective client.
Good to know
A watermark is a deterrent, not security. The text is drawn over the page, the document underneath remains perfectly readable, and anyone determined enough can strip or crop it. Treat it as a label that discourages casual misuse and makes the source obvious — nothing more. If you need the document to actually stay shut, Protect PDF encrypts it with a password, and the two work well together: a watermark for the people you meant to send it to, a password for everyone else.
Some practical notes. The stamp is a single line of text in the centre of each page, not a repeating tile, and it goes on every page — there is no way to skip some. It uses the standard Helvetica Bold built into the PDF format, which covers Latin letters, digits and common punctuation; unusual accented or non-Latin characters may fail to draw. Nothing is uploaded at any stage: the file is opened, stamped and saved by JavaScript running in this tab, so a confidential report stays confidential while you are marking it as such. If you also want each page identifiable by number, Add Page Numbers does that on the same principle.
Questions people ask
What opacity should I choose?
The default 30% is legible without fighting the text underneath. Drop towards 10-15% for dense pages that still need comfortable reading, and push above 50% only when the mark must dominate — printed at high opacity it will obscure whatever sits behind it.
Can I remove the watermark later?
Not with this tool, and not easily with any other. The text becomes part of the page content when the file is saved. Keep your unwatermarked original — stamp a copy, never your only version.
Can I use an image or logo instead of text?
Not here; this tool draws text only. For a logo, Sign PDF can place a drawn mark on a single page, though it is designed for signatures rather than repeated branding.
Will it work on a scanned PDF?
Yes. The watermark is drawn on top of the page whether that page is real text or a scanned image, so scans, photographs and exported presentations all take the stamp the same way.